Hi,
Am 17.02.2020 um 12:24 schrieb Chanwoo Choi cw00.choi@samsung.com:
Hi,
On 2/17/20 8:07 PM, H. Nikolaus Schaller wrote:
Hi Chanwoo Choi,
Am 17.02.2020 um 11:15 schrieb Chanwoo Choi cw00.choi@samsung.com:
Hi,
On 2/17/20 5:55 PM, H. Nikolaus Schaller wrote:
If the gpios are probed after this driver (e.g. if they come from an i2c expander) there is no need to print an error message.
Signed-off-by: H. Nikolaus Schaller hns@goldelico.com
drivers/extcon/extcon-palmas.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/extcon/extcon-palmas.c b/drivers/extcon/extcon-palmas.c index edc5016f46f1..9c6254c0531c 100644 --- a/drivers/extcon/extcon-palmas.c +++ b/drivers/extcon/extcon-palmas.c @@ -206,14 +206,16 @@ static int palmas_usb_probe(struct platform_device *pdev) palmas_usb->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id", GPIOD_IN); if (IS_ERR(palmas_usb->id_gpiod)) {
dev_err(&pdev->dev, "failed to get id gpio\n");
if (PTR_ERR(palmas_usb->id_gpiod) != -EPROBE_DEFER)dev_err(&pdev->dev, "failed to get id gpio\n");How about editing it ? as following: because following suggestion reduces the one checking behavior when return value is -EPROBE_DEFER.
if (PTR_ERR(palmas_usb->id_gpiod) == -EPROBE_DEFER) { return -EPROBE_DEFER; } else if (IS_ERR(palmas_usb->id_gpiod)) { dev_err(&pdev->dev, "failed to get id gpio\n"); return PTR_ERR(palmas_usb->id_gpiod); }
Yes, looks indeed to be valid (some discussion around is here: https://lore.kernel.org/patchwork/patch/999602/ ).
So I'll send an update asap.
palmas_usb->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus", GPIOD_IN); if (IS_ERR(palmas_usb->vbus_gpiod)) {
dev_err(&pdev->dev, "failed to get vbus gpio\n");
if (PTR_ERR(palmas_usb->vbus_gpiod) != -EPROBE_DEFER)dev_err(&pdev->dev, "failed to get vbus gpio\n");ditto.
return PTR_ERR(palmas_usb->vbus_gpiod);}
Usually, gpio driver like pinctrl is very early probed because almost device drivers should use gpio. So, I have not any experience about this situation. Do you meet this situation on any h/w board?
Yes, I have experienced that sometimes on omap5+palmas based boards.
It seems to be this:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch...
The extcon_usb3 can potentially match this extcon-palmas driver at a moment where the palmas_gpio it is referring to has not yet been successfully probed. Then the palmas_gpio would return -EPROBE_DEFER.
AFAIK there is no guarantee for a specific sequence of drivers being probed and it is pure luck that in most cases the gpios are already probed.
Thanks for explaining the example.
BR and thanks, Nikolaus Schaller